IIT JEE Advanced & Mains Physics 2018 : Electricity : Rank file / expected questions : VI

IIT JEE Advanced & Mains Physics 2018 : Electricity : Rank file / expected questions / Physicsmynd Elite Series  /  Page  VI 

Primary Users : Students appearing for the Advanced and Mains Exam for Admission to the BTech Courses at the Indian Institutes of Technology , National Institutes of Technology , Indian Institute of Space science and Technology and other National Engineering Institutes, INDIA .

Secondary Users : GATE Physics  , JAM Physics , Physics paper of Civil Services Exam , UGC – NET Physics , National and International Physics Olympiads,International College level Physics Exams, Indian State Board Engineering entrance exams etc.

Tertiary Users : All those who love Physics !

Answers with full explanations and tips & tricks to solve similar problems to be published in our site https://physicsmynd.in ]

To view  more problems visit https://physicsmynd.in/electricity/

Page  : 6

46 – 47 ] A  cylindrical coaxial capacitor having an inner and outer conductors of radius a  and b respectively , is charged to a voltage V . It’s  dielectric constant K(r) of it’s dielectric  varies with it’s cylindrical radius r . Then – 

 Find the radial dependence of it’s dielectric constant.

47 ] In the above question ,the electric field E(r) is given by –

A ] E(r)=\frac {2rV}{{b}^{{3}}+{a}^{{2}}}

B ] E(r)=-\frac {2rV}{{b}^{{3}}+{a}^{{2}}}

C ] E(r)=\frac {2rV}{{b}^{{2}}-{a}^{{2}}}

D ] E(r)=-\frac {2rV}{{b}^{{2}}-{a}^{{2}}}

48 ] A system consists of three point charges – 3nC , 2nC and 5nC , at  locations  (0, 0, 0), (0, 0, 1), and (1, 0, 0), respectively.Then the energy of this system is –

A ]  W =9\left({\frac {10}{\sqrt{{2}}}-15}\right) nJ

B ]  W =9\left({\frac {6}{\sqrt{{2}}}-7}\right) nJ

C ]  W =9\left({\frac {5}{\sqrt{{2}}}-10}\right) nJ

D ]  W =9\left({\frac {15}{\sqrt{{2}}}-6}\right) nJ

49 – 50 ] A charge Q is equally divided between three identical tiny spheres of mass m which are suspended by threads of negligible masses and equal length l from a common point. If they come to equilibrium at the corners of a horizontal equilateral triangle whose sides are d ,then {Q}^{2} is proportional to –

A ]  12\pi {\epsilon } _{0}

B ]  8\pi {\epsilon } _{0}

C ]  24\pi {\epsilon } _{0}

D ]  10\pi {\epsilon } _{0}

50 ] In the above arrangement , find Q ? 

51 – 54 ] The figure below shows a charged ring of radius R , into the center of which , an  electron e is brought in through a distance x .  Questions 51 – 54 are based on this –

51] The acceleration experienced by the electron is proportional to –

A ]  \frac{1}{{R}^{{4}}}

B ]  \frac{1}{{R}^{{2}}}

C ]  \frac{1}{{R}^{{3}}}

D ]  \frac{1}{{R}}

52 ] At what distance from the center of the ring is the electric field maximum ? 

53 ] Does the electron experience SHM [ simple harmonic motion ] ?

54 ] If it experiences SHM ,then find the tension , T , acting on the electron ?  

Comments are closed.